xref: /openbmc/linux/drivers/gpu/drm/tegra/dsi.c (revision 08283d30)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2013 NVIDIA Corporation
4  */
5 
6 #include <linux/clk.h>
7 #include <linux/debugfs.h>
8 #include <linux/delay.h>
9 #include <linux/host1x.h>
10 #include <linux/module.h>
11 #include <linux/of.h>
12 #include <linux/of_platform.h>
13 #include <linux/platform_device.h>
14 #include <linux/pm_runtime.h>
15 #include <linux/regulator/consumer.h>
16 #include <linux/reset.h>
17 
18 #include <video/mipi_display.h>
19 
20 #include <drm/drm_atomic_helper.h>
21 #include <drm/drm_debugfs.h>
22 #include <drm/drm_file.h>
23 #include <drm/drm_mipi_dsi.h>
24 #include <drm/drm_panel.h>
25 
26 #include "dc.h"
27 #include "drm.h"
28 #include "dsi.h"
29 #include "mipi-phy.h"
30 #include "trace.h"
31 
32 struct tegra_dsi_state {
33 	struct drm_connector_state base;
34 
35 	struct mipi_dphy_timing timing;
36 	unsigned long period;
37 
38 	unsigned int vrefresh;
39 	unsigned int lanes;
40 	unsigned long pclk;
41 	unsigned long bclk;
42 
43 	enum tegra_dsi_format format;
44 	unsigned int mul;
45 	unsigned int div;
46 };
47 
48 static inline struct tegra_dsi_state *
49 to_dsi_state(struct drm_connector_state *state)
50 {
51 	return container_of(state, struct tegra_dsi_state, base);
52 }
53 
54 struct tegra_dsi {
55 	struct host1x_client client;
56 	struct tegra_output output;
57 	struct device *dev;
58 
59 	void __iomem *regs;
60 
61 	struct reset_control *rst;
62 	struct clk *clk_parent;
63 	struct clk *clk_lp;
64 	struct clk *clk;
65 
66 	struct drm_info_list *debugfs_files;
67 
68 	unsigned long flags;
69 	enum mipi_dsi_pixel_format format;
70 	unsigned int lanes;
71 
72 	struct tegra_mipi_device *mipi;
73 	struct mipi_dsi_host host;
74 
75 	struct regulator *vdd;
76 
77 	unsigned int video_fifo_depth;
78 	unsigned int host_fifo_depth;
79 
80 	/* for ganged-mode support */
81 	struct tegra_dsi *master;
82 	struct tegra_dsi *slave;
83 };
84 
85 static inline struct tegra_dsi *
86 host1x_client_to_dsi(struct host1x_client *client)
87 {
88 	return container_of(client, struct tegra_dsi, client);
89 }
90 
91 static inline struct tegra_dsi *host_to_tegra(struct mipi_dsi_host *host)
92 {
93 	return container_of(host, struct tegra_dsi, host);
94 }
95 
96 static inline struct tegra_dsi *to_dsi(struct tegra_output *output)
97 {
98 	return container_of(output, struct tegra_dsi, output);
99 }
100 
101 static struct tegra_dsi_state *tegra_dsi_get_state(struct tegra_dsi *dsi)
102 {
103 	return to_dsi_state(dsi->output.connector.state);
104 }
105 
106 static inline u32 tegra_dsi_readl(struct tegra_dsi *dsi, unsigned int offset)
107 {
108 	u32 value = readl(dsi->regs + (offset << 2));
109 
110 	trace_dsi_readl(dsi->dev, offset, value);
111 
112 	return value;
113 }
114 
115 static inline void tegra_dsi_writel(struct tegra_dsi *dsi, u32 value,
116 				    unsigned int offset)
117 {
118 	trace_dsi_writel(dsi->dev, offset, value);
119 	writel(value, dsi->regs + (offset << 2));
120 }
121 
122 #define DEBUGFS_REG32(_name) { .name = #_name, .offset = _name }
123 
124 static const struct debugfs_reg32 tegra_dsi_regs[] = {
125 	DEBUGFS_REG32(DSI_INCR_SYNCPT),
126 	DEBUGFS_REG32(DSI_INCR_SYNCPT_CONTROL),
127 	DEBUGFS_REG32(DSI_INCR_SYNCPT_ERROR),
128 	DEBUGFS_REG32(DSI_CTXSW),
129 	DEBUGFS_REG32(DSI_RD_DATA),
130 	DEBUGFS_REG32(DSI_WR_DATA),
131 	DEBUGFS_REG32(DSI_POWER_CONTROL),
132 	DEBUGFS_REG32(DSI_INT_ENABLE),
133 	DEBUGFS_REG32(DSI_INT_STATUS),
134 	DEBUGFS_REG32(DSI_INT_MASK),
135 	DEBUGFS_REG32(DSI_HOST_CONTROL),
136 	DEBUGFS_REG32(DSI_CONTROL),
137 	DEBUGFS_REG32(DSI_SOL_DELAY),
138 	DEBUGFS_REG32(DSI_MAX_THRESHOLD),
139 	DEBUGFS_REG32(DSI_TRIGGER),
140 	DEBUGFS_REG32(DSI_TX_CRC),
141 	DEBUGFS_REG32(DSI_STATUS),
142 	DEBUGFS_REG32(DSI_INIT_SEQ_CONTROL),
143 	DEBUGFS_REG32(DSI_INIT_SEQ_DATA_0),
144 	DEBUGFS_REG32(DSI_INIT_SEQ_DATA_1),
145 	DEBUGFS_REG32(DSI_INIT_SEQ_DATA_2),
146 	DEBUGFS_REG32(DSI_INIT_SEQ_DATA_3),
147 	DEBUGFS_REG32(DSI_INIT_SEQ_DATA_4),
148 	DEBUGFS_REG32(DSI_INIT_SEQ_DATA_5),
149 	DEBUGFS_REG32(DSI_INIT_SEQ_DATA_6),
150 	DEBUGFS_REG32(DSI_INIT_SEQ_DATA_7),
151 	DEBUGFS_REG32(DSI_PKT_SEQ_0_LO),
152 	DEBUGFS_REG32(DSI_PKT_SEQ_0_HI),
153 	DEBUGFS_REG32(DSI_PKT_SEQ_1_LO),
154 	DEBUGFS_REG32(DSI_PKT_SEQ_1_HI),
155 	DEBUGFS_REG32(DSI_PKT_SEQ_2_LO),
156 	DEBUGFS_REG32(DSI_PKT_SEQ_2_HI),
157 	DEBUGFS_REG32(DSI_PKT_SEQ_3_LO),
158 	DEBUGFS_REG32(DSI_PKT_SEQ_3_HI),
159 	DEBUGFS_REG32(DSI_PKT_SEQ_4_LO),
160 	DEBUGFS_REG32(DSI_PKT_SEQ_4_HI),
161 	DEBUGFS_REG32(DSI_PKT_SEQ_5_LO),
162 	DEBUGFS_REG32(DSI_PKT_SEQ_5_HI),
163 	DEBUGFS_REG32(DSI_DCS_CMDS),
164 	DEBUGFS_REG32(DSI_PKT_LEN_0_1),
165 	DEBUGFS_REG32(DSI_PKT_LEN_2_3),
166 	DEBUGFS_REG32(DSI_PKT_LEN_4_5),
167 	DEBUGFS_REG32(DSI_PKT_LEN_6_7),
168 	DEBUGFS_REG32(DSI_PHY_TIMING_0),
169 	DEBUGFS_REG32(DSI_PHY_TIMING_1),
170 	DEBUGFS_REG32(DSI_PHY_TIMING_2),
171 	DEBUGFS_REG32(DSI_BTA_TIMING),
172 	DEBUGFS_REG32(DSI_TIMEOUT_0),
173 	DEBUGFS_REG32(DSI_TIMEOUT_1),
174 	DEBUGFS_REG32(DSI_TO_TALLY),
175 	DEBUGFS_REG32(DSI_PAD_CONTROL_0),
176 	DEBUGFS_REG32(DSI_PAD_CONTROL_CD),
177 	DEBUGFS_REG32(DSI_PAD_CD_STATUS),
178 	DEBUGFS_REG32(DSI_VIDEO_MODE_CONTROL),
179 	DEBUGFS_REG32(DSI_PAD_CONTROL_1),
180 	DEBUGFS_REG32(DSI_PAD_CONTROL_2),
181 	DEBUGFS_REG32(DSI_PAD_CONTROL_3),
182 	DEBUGFS_REG32(DSI_PAD_CONTROL_4),
183 	DEBUGFS_REG32(DSI_GANGED_MODE_CONTROL),
184 	DEBUGFS_REG32(DSI_GANGED_MODE_START),
185 	DEBUGFS_REG32(DSI_GANGED_MODE_SIZE),
186 	DEBUGFS_REG32(DSI_RAW_DATA_BYTE_COUNT),
187 	DEBUGFS_REG32(DSI_ULTRA_LOW_POWER_CONTROL),
188 	DEBUGFS_REG32(DSI_INIT_SEQ_DATA_8),
189 	DEBUGFS_REG32(DSI_INIT_SEQ_DATA_9),
190 	DEBUGFS_REG32(DSI_INIT_SEQ_DATA_10),
191 	DEBUGFS_REG32(DSI_INIT_SEQ_DATA_11),
192 	DEBUGFS_REG32(DSI_INIT_SEQ_DATA_12),
193 	DEBUGFS_REG32(DSI_INIT_SEQ_DATA_13),
194 	DEBUGFS_REG32(DSI_INIT_SEQ_DATA_14),
195 	DEBUGFS_REG32(DSI_INIT_SEQ_DATA_15),
196 };
197 
198 static int tegra_dsi_show_regs(struct seq_file *s, void *data)
199 {
200 	struct drm_info_node *node = s->private;
201 	struct tegra_dsi *dsi = node->info_ent->data;
202 	struct drm_crtc *crtc = dsi->output.encoder.crtc;
203 	struct drm_device *drm = node->minor->dev;
204 	unsigned int i;
205 	int err = 0;
206 
207 	drm_modeset_lock_all(drm);
208 
209 	if (!crtc || !crtc->state->active) {
210 		err = -EBUSY;
211 		goto unlock;
212 	}
213 
214 	for (i = 0; i < ARRAY_SIZE(tegra_dsi_regs); i++) {
215 		unsigned int offset = tegra_dsi_regs[i].offset;
216 
217 		seq_printf(s, "%-32s %#05x %08x\n", tegra_dsi_regs[i].name,
218 			   offset, tegra_dsi_readl(dsi, offset));
219 	}
220 
221 unlock:
222 	drm_modeset_unlock_all(drm);
223 	return err;
224 }
225 
226 static struct drm_info_list debugfs_files[] = {
227 	{ "regs", tegra_dsi_show_regs, 0, NULL },
228 };
229 
230 static int tegra_dsi_late_register(struct drm_connector *connector)
231 {
232 	struct tegra_output *output = connector_to_output(connector);
233 	unsigned int i, count = ARRAY_SIZE(debugfs_files);
234 	struct drm_minor *minor = connector->dev->primary;
235 	struct dentry *root = connector->debugfs_entry;
236 	struct tegra_dsi *dsi = to_dsi(output);
237 	int err;
238 
239 	dsi->debugfs_files = kmemdup(debugfs_files, sizeof(debugfs_files),
240 				     GFP_KERNEL);
241 	if (!dsi->debugfs_files)
242 		return -ENOMEM;
243 
244 	for (i = 0; i < count; i++)
245 		dsi->debugfs_files[i].data = dsi;
246 
247 	err = drm_debugfs_create_files(dsi->debugfs_files, count, root, minor);
248 	if (err < 0)
249 		goto free;
250 
251 	return 0;
252 
253 free:
254 	kfree(dsi->debugfs_files);
255 	dsi->debugfs_files = NULL;
256 
257 	return err;
258 }
259 
260 static void tegra_dsi_early_unregister(struct drm_connector *connector)
261 {
262 	struct tegra_output *output = connector_to_output(connector);
263 	unsigned int count = ARRAY_SIZE(debugfs_files);
264 	struct tegra_dsi *dsi = to_dsi(output);
265 
266 	drm_debugfs_remove_files(dsi->debugfs_files, count,
267 				 connector->dev->primary);
268 	kfree(dsi->debugfs_files);
269 	dsi->debugfs_files = NULL;
270 }
271 
272 #define PKT_ID0(id)	((((id) & 0x3f) <<  3) | (1 <<  9))
273 #define PKT_LEN0(len)	(((len) & 0x07) <<  0)
274 #define PKT_ID1(id)	((((id) & 0x3f) << 13) | (1 << 19))
275 #define PKT_LEN1(len)	(((len) & 0x07) << 10)
276 #define PKT_ID2(id)	((((id) & 0x3f) << 23) | (1 << 29))
277 #define PKT_LEN2(len)	(((len) & 0x07) << 20)
278 
279 #define PKT_LP		(1 << 30)
280 #define NUM_PKT_SEQ	12
281 
282 /*
283  * non-burst mode with sync pulses
284  */
285 static const u32 pkt_seq_video_non_burst_sync_pulses[NUM_PKT_SEQ] = {
286 	[ 0] = PKT_ID0(MIPI_DSI_V_SYNC_START) | PKT_LEN0(0) |
287 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(1) |
288 	       PKT_ID2(MIPI_DSI_H_SYNC_END) | PKT_LEN2(0) |
289 	       PKT_LP,
290 	[ 1] = 0,
291 	[ 2] = PKT_ID0(MIPI_DSI_V_SYNC_END) | PKT_LEN0(0) |
292 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(1) |
293 	       PKT_ID2(MIPI_DSI_H_SYNC_END) | PKT_LEN2(0) |
294 	       PKT_LP,
295 	[ 3] = 0,
296 	[ 4] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
297 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(1) |
298 	       PKT_ID2(MIPI_DSI_H_SYNC_END) | PKT_LEN2(0) |
299 	       PKT_LP,
300 	[ 5] = 0,
301 	[ 6] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
302 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(1) |
303 	       PKT_ID2(MIPI_DSI_H_SYNC_END) | PKT_LEN2(0),
304 	[ 7] = PKT_ID0(MIPI_DSI_BLANKING_PACKET) | PKT_LEN0(2) |
305 	       PKT_ID1(MIPI_DSI_PACKED_PIXEL_STREAM_24) | PKT_LEN1(3) |
306 	       PKT_ID2(MIPI_DSI_BLANKING_PACKET) | PKT_LEN2(4),
307 	[ 8] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
308 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(1) |
309 	       PKT_ID2(MIPI_DSI_H_SYNC_END) | PKT_LEN2(0) |
310 	       PKT_LP,
311 	[ 9] = 0,
312 	[10] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
313 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(1) |
314 	       PKT_ID2(MIPI_DSI_H_SYNC_END) | PKT_LEN2(0),
315 	[11] = PKT_ID0(MIPI_DSI_BLANKING_PACKET) | PKT_LEN0(2) |
316 	       PKT_ID1(MIPI_DSI_PACKED_PIXEL_STREAM_24) | PKT_LEN1(3) |
317 	       PKT_ID2(MIPI_DSI_BLANKING_PACKET) | PKT_LEN2(4),
318 };
319 
320 /*
321  * non-burst mode with sync events
322  */
323 static const u32 pkt_seq_video_non_burst_sync_events[NUM_PKT_SEQ] = {
324 	[ 0] = PKT_ID0(MIPI_DSI_V_SYNC_START) | PKT_LEN0(0) |
325 	       PKT_ID1(MIPI_DSI_END_OF_TRANSMISSION) | PKT_LEN1(7) |
326 	       PKT_LP,
327 	[ 1] = 0,
328 	[ 2] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
329 	       PKT_ID1(MIPI_DSI_END_OF_TRANSMISSION) | PKT_LEN1(7) |
330 	       PKT_LP,
331 	[ 3] = 0,
332 	[ 4] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
333 	       PKT_ID1(MIPI_DSI_END_OF_TRANSMISSION) | PKT_LEN1(7) |
334 	       PKT_LP,
335 	[ 5] = 0,
336 	[ 6] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
337 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(2) |
338 	       PKT_ID2(MIPI_DSI_PACKED_PIXEL_STREAM_24) | PKT_LEN2(3),
339 	[ 7] = PKT_ID0(MIPI_DSI_BLANKING_PACKET) | PKT_LEN0(4),
340 	[ 8] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
341 	       PKT_ID1(MIPI_DSI_END_OF_TRANSMISSION) | PKT_LEN1(7) |
342 	       PKT_LP,
343 	[ 9] = 0,
344 	[10] = PKT_ID0(MIPI_DSI_H_SYNC_START) | PKT_LEN0(0) |
345 	       PKT_ID1(MIPI_DSI_BLANKING_PACKET) | PKT_LEN1(2) |
346 	       PKT_ID2(MIPI_DSI_PACKED_PIXEL_STREAM_24) | PKT_LEN2(3),
347 	[11] = PKT_ID0(MIPI_DSI_BLANKING_PACKET) | PKT_LEN0(4),
348 };
349 
350 static const u32 pkt_seq_command_mode[NUM_PKT_SEQ] = {
351 	[ 0] = 0,
352 	[ 1] = 0,
353 	[ 2] = 0,
354 	[ 3] = 0,
355 	[ 4] = 0,
356 	[ 5] = 0,
357 	[ 6] = PKT_ID0(MIPI_DSI_DCS_LONG_WRITE) | PKT_LEN0(3) | PKT_LP,
358 	[ 7] = 0,
359 	[ 8] = 0,
360 	[ 9] = 0,
361 	[10] = PKT_ID0(MIPI_DSI_DCS_LONG_WRITE) | PKT_LEN0(5) | PKT_LP,
362 	[11] = 0,
363 };
364 
365 static void tegra_dsi_set_phy_timing(struct tegra_dsi *dsi,
366 				     unsigned long period,
367 				     const struct mipi_dphy_timing *timing)
368 {
369 	u32 value;
370 
371 	value = DSI_TIMING_FIELD(timing->hsexit, period, 1) << 24 |
372 		DSI_TIMING_FIELD(timing->hstrail, period, 0) << 16 |
373 		DSI_TIMING_FIELD(timing->hszero, period, 3) << 8 |
374 		DSI_TIMING_FIELD(timing->hsprepare, period, 1);
375 	tegra_dsi_writel(dsi, value, DSI_PHY_TIMING_0);
376 
377 	value = DSI_TIMING_FIELD(timing->clktrail, period, 1) << 24 |
378 		DSI_TIMING_FIELD(timing->clkpost, period, 1) << 16 |
379 		DSI_TIMING_FIELD(timing->clkzero, period, 1) << 8 |
380 		DSI_TIMING_FIELD(timing->lpx, period, 1);
381 	tegra_dsi_writel(dsi, value, DSI_PHY_TIMING_1);
382 
383 	value = DSI_TIMING_FIELD(timing->clkprepare, period, 1) << 16 |
384 		DSI_TIMING_FIELD(timing->clkpre, period, 1) << 8 |
385 		DSI_TIMING_FIELD(0xff * period, period, 0) << 0;
386 	tegra_dsi_writel(dsi, value, DSI_PHY_TIMING_2);
387 
388 	value = DSI_TIMING_FIELD(timing->taget, period, 1) << 16 |
389 		DSI_TIMING_FIELD(timing->tasure, period, 1) << 8 |
390 		DSI_TIMING_FIELD(timing->tago, period, 1);
391 	tegra_dsi_writel(dsi, value, DSI_BTA_TIMING);
392 
393 	if (dsi->slave)
394 		tegra_dsi_set_phy_timing(dsi->slave, period, timing);
395 }
396 
397 static int tegra_dsi_get_muldiv(enum mipi_dsi_pixel_format format,
398 				unsigned int *mulp, unsigned int *divp)
399 {
400 	switch (format) {
401 	case MIPI_DSI_FMT_RGB666_PACKED:
402 	case MIPI_DSI_FMT_RGB888:
403 		*mulp = 3;
404 		*divp = 1;
405 		break;
406 
407 	case MIPI_DSI_FMT_RGB565:
408 		*mulp = 2;
409 		*divp = 1;
410 		break;
411 
412 	case MIPI_DSI_FMT_RGB666:
413 		*mulp = 9;
414 		*divp = 4;
415 		break;
416 
417 	default:
418 		return -EINVAL;
419 	}
420 
421 	return 0;
422 }
423 
424 static int tegra_dsi_get_format(enum mipi_dsi_pixel_format format,
425 				enum tegra_dsi_format *fmt)
426 {
427 	switch (format) {
428 	case MIPI_DSI_FMT_RGB888:
429 		*fmt = TEGRA_DSI_FORMAT_24P;
430 		break;
431 
432 	case MIPI_DSI_FMT_RGB666:
433 		*fmt = TEGRA_DSI_FORMAT_18NP;
434 		break;
435 
436 	case MIPI_DSI_FMT_RGB666_PACKED:
437 		*fmt = TEGRA_DSI_FORMAT_18P;
438 		break;
439 
440 	case MIPI_DSI_FMT_RGB565:
441 		*fmt = TEGRA_DSI_FORMAT_16P;
442 		break;
443 
444 	default:
445 		return -EINVAL;
446 	}
447 
448 	return 0;
449 }
450 
451 static void tegra_dsi_ganged_enable(struct tegra_dsi *dsi, unsigned int start,
452 				    unsigned int size)
453 {
454 	u32 value;
455 
456 	tegra_dsi_writel(dsi, start, DSI_GANGED_MODE_START);
457 	tegra_dsi_writel(dsi, size << 16 | size, DSI_GANGED_MODE_SIZE);
458 
459 	value = DSI_GANGED_MODE_CONTROL_ENABLE;
460 	tegra_dsi_writel(dsi, value, DSI_GANGED_MODE_CONTROL);
461 }
462 
463 static void tegra_dsi_enable(struct tegra_dsi *dsi)
464 {
465 	u32 value;
466 
467 	value = tegra_dsi_readl(dsi, DSI_POWER_CONTROL);
468 	value |= DSI_POWER_CONTROL_ENABLE;
469 	tegra_dsi_writel(dsi, value, DSI_POWER_CONTROL);
470 
471 	if (dsi->slave)
472 		tegra_dsi_enable(dsi->slave);
473 }
474 
475 static unsigned int tegra_dsi_get_lanes(struct tegra_dsi *dsi)
476 {
477 	if (dsi->master)
478 		return dsi->master->lanes + dsi->lanes;
479 
480 	if (dsi->slave)
481 		return dsi->lanes + dsi->slave->lanes;
482 
483 	return dsi->lanes;
484 }
485 
486 static void tegra_dsi_configure(struct tegra_dsi *dsi, unsigned int pipe,
487 				const struct drm_display_mode *mode)
488 {
489 	unsigned int hact, hsw, hbp, hfp, i, mul, div;
490 	struct tegra_dsi_state *state;
491 	const u32 *pkt_seq;
492 	u32 value;
493 
494 	/* XXX: pass in state into this function? */
495 	if (dsi->master)
496 		state = tegra_dsi_get_state(dsi->master);
497 	else
498 		state = tegra_dsi_get_state(dsi);
499 
500 	mul = state->mul;
501 	div = state->div;
502 
503 	if (dsi->flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) {
504 		DRM_DEBUG_KMS("Non-burst video mode with sync pulses\n");
505 		pkt_seq = pkt_seq_video_non_burst_sync_pulses;
506 	} else if (dsi->flags & MIPI_DSI_MODE_VIDEO) {
507 		DRM_DEBUG_KMS("Non-burst video mode with sync events\n");
508 		pkt_seq = pkt_seq_video_non_burst_sync_events;
509 	} else {
510 		DRM_DEBUG_KMS("Command mode\n");
511 		pkt_seq = pkt_seq_command_mode;
512 	}
513 
514 	value = DSI_CONTROL_CHANNEL(0) |
515 		DSI_CONTROL_FORMAT(state->format) |
516 		DSI_CONTROL_LANES(dsi->lanes - 1) |
517 		DSI_CONTROL_SOURCE(pipe);
518 	tegra_dsi_writel(dsi, value, DSI_CONTROL);
519 
520 	tegra_dsi_writel(dsi, dsi->video_fifo_depth, DSI_MAX_THRESHOLD);
521 
522 	value = DSI_HOST_CONTROL_HS;
523 	tegra_dsi_writel(dsi, value, DSI_HOST_CONTROL);
524 
525 	value = tegra_dsi_readl(dsi, DSI_CONTROL);
526 
527 	if (dsi->flags & MIPI_DSI_CLOCK_NON_CONTINUOUS)
528 		value |= DSI_CONTROL_HS_CLK_CTRL;
529 
530 	value &= ~DSI_CONTROL_TX_TRIG(3);
531 
532 	/* enable DCS commands for command mode */
533 	if (dsi->flags & MIPI_DSI_MODE_VIDEO)
534 		value &= ~DSI_CONTROL_DCS_ENABLE;
535 	else
536 		value |= DSI_CONTROL_DCS_ENABLE;
537 
538 	value |= DSI_CONTROL_VIDEO_ENABLE;
539 	value &= ~DSI_CONTROL_HOST_ENABLE;
540 	tegra_dsi_writel(dsi, value, DSI_CONTROL);
541 
542 	for (i = 0; i < NUM_PKT_SEQ; i++)
543 		tegra_dsi_writel(dsi, pkt_seq[i], DSI_PKT_SEQ_0_LO + i);
544 
545 	if (dsi->flags & MIPI_DSI_MODE_VIDEO) {
546 		/* horizontal active pixels */
547 		hact = mode->hdisplay * mul / div;
548 
549 		/* horizontal sync width */
550 		hsw = (mode->hsync_end - mode->hsync_start) * mul / div;
551 
552 		/* horizontal back porch */
553 		hbp = (mode->htotal - mode->hsync_end) * mul / div;
554 
555 		if ((dsi->flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) == 0)
556 			hbp += hsw;
557 
558 		/* horizontal front porch */
559 		hfp = (mode->hsync_start - mode->hdisplay) * mul / div;
560 
561 		/* subtract packet overhead */
562 		hsw -= 10;
563 		hbp -= 14;
564 		hfp -= 8;
565 
566 		tegra_dsi_writel(dsi, hsw << 16 | 0, DSI_PKT_LEN_0_1);
567 		tegra_dsi_writel(dsi, hact << 16 | hbp, DSI_PKT_LEN_2_3);
568 		tegra_dsi_writel(dsi, hfp, DSI_PKT_LEN_4_5);
569 		tegra_dsi_writel(dsi, 0x0f0f << 16, DSI_PKT_LEN_6_7);
570 
571 		/* set SOL delay (for non-burst mode only) */
572 		tegra_dsi_writel(dsi, 8 * mul / div, DSI_SOL_DELAY);
573 
574 		/* TODO: implement ganged mode */
575 	} else {
576 		u16 bytes;
577 
578 		if (dsi->master || dsi->slave) {
579 			/*
580 			 * For ganged mode, assume symmetric left-right mode.
581 			 */
582 			bytes = 1 + (mode->hdisplay / 2) * mul / div;
583 		} else {
584 			/* 1 byte (DCS command) + pixel data */
585 			bytes = 1 + mode->hdisplay * mul / div;
586 		}
587 
588 		tegra_dsi_writel(dsi, 0, DSI_PKT_LEN_0_1);
589 		tegra_dsi_writel(dsi, bytes << 16, DSI_PKT_LEN_2_3);
590 		tegra_dsi_writel(dsi, bytes << 16, DSI_PKT_LEN_4_5);
591 		tegra_dsi_writel(dsi, 0, DSI_PKT_LEN_6_7);
592 
593 		value = MIPI_DCS_WRITE_MEMORY_START << 8 |
594 			MIPI_DCS_WRITE_MEMORY_CONTINUE;
595 		tegra_dsi_writel(dsi, value, DSI_DCS_CMDS);
596 
597 		/* set SOL delay */
598 		if (dsi->master || dsi->slave) {
599 			unsigned long delay, bclk, bclk_ganged;
600 			unsigned int lanes = state->lanes;
601 
602 			/* SOL to valid, valid to FIFO and FIFO write delay */
603 			delay = 4 + 4 + 2;
604 			delay = DIV_ROUND_UP(delay * mul, div * lanes);
605 			/* FIFO read delay */
606 			delay = delay + 6;
607 
608 			bclk = DIV_ROUND_UP(mode->htotal * mul, div * lanes);
609 			bclk_ganged = DIV_ROUND_UP(bclk * lanes / 2, lanes);
610 			value = bclk - bclk_ganged + delay + 20;
611 		} else {
612 			/* TODO: revisit for non-ganged mode */
613 			value = 8 * mul / div;
614 		}
615 
616 		tegra_dsi_writel(dsi, value, DSI_SOL_DELAY);
617 	}
618 
619 	if (dsi->slave) {
620 		tegra_dsi_configure(dsi->slave, pipe, mode);
621 
622 		/*
623 		 * TODO: Support modes other than symmetrical left-right
624 		 * split.
625 		 */
626 		tegra_dsi_ganged_enable(dsi, 0, mode->hdisplay / 2);
627 		tegra_dsi_ganged_enable(dsi->slave, mode->hdisplay / 2,
628 					mode->hdisplay / 2);
629 	}
630 }
631 
632 static int tegra_dsi_wait_idle(struct tegra_dsi *dsi, unsigned long timeout)
633 {
634 	u32 value;
635 
636 	timeout = jiffies + msecs_to_jiffies(timeout);
637 
638 	while (time_before(jiffies, timeout)) {
639 		value = tegra_dsi_readl(dsi, DSI_STATUS);
640 		if (value & DSI_STATUS_IDLE)
641 			return 0;
642 
643 		usleep_range(1000, 2000);
644 	}
645 
646 	return -ETIMEDOUT;
647 }
648 
649 static void tegra_dsi_video_disable(struct tegra_dsi *dsi)
650 {
651 	u32 value;
652 
653 	value = tegra_dsi_readl(dsi, DSI_CONTROL);
654 	value &= ~DSI_CONTROL_VIDEO_ENABLE;
655 	tegra_dsi_writel(dsi, value, DSI_CONTROL);
656 
657 	if (dsi->slave)
658 		tegra_dsi_video_disable(dsi->slave);
659 }
660 
661 static void tegra_dsi_ganged_disable(struct tegra_dsi *dsi)
662 {
663 	tegra_dsi_writel(dsi, 0, DSI_GANGED_MODE_START);
664 	tegra_dsi_writel(dsi, 0, DSI_GANGED_MODE_SIZE);
665 	tegra_dsi_writel(dsi, 0, DSI_GANGED_MODE_CONTROL);
666 }
667 
668 static int tegra_dsi_pad_enable(struct tegra_dsi *dsi)
669 {
670 	u32 value;
671 
672 	value = DSI_PAD_CONTROL_VS1_PULLDN(0) | DSI_PAD_CONTROL_VS1_PDIO(0);
673 	tegra_dsi_writel(dsi, value, DSI_PAD_CONTROL_0);
674 
675 	return 0;
676 }
677 
678 static int tegra_dsi_pad_calibrate(struct tegra_dsi *dsi)
679 {
680 	u32 value;
681 
682 	/*
683 	 * XXX Is this still needed? The module reset is deasserted right
684 	 * before this function is called.
685 	 */
686 	tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_0);
687 	tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_1);
688 	tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_2);
689 	tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_3);
690 	tegra_dsi_writel(dsi, 0, DSI_PAD_CONTROL_4);
691 
692 	/* start calibration */
693 	tegra_dsi_pad_enable(dsi);
694 
695 	value = DSI_PAD_SLEW_UP(0x7) | DSI_PAD_SLEW_DN(0x7) |
696 		DSI_PAD_LP_UP(0x1) | DSI_PAD_LP_DN(0x1) |
697 		DSI_PAD_OUT_CLK(0x0);
698 	tegra_dsi_writel(dsi, value, DSI_PAD_CONTROL_2);
699 
700 	value = DSI_PAD_PREEMP_PD_CLK(0x3) | DSI_PAD_PREEMP_PU_CLK(0x3) |
701 		DSI_PAD_PREEMP_PD(0x03) | DSI_PAD_PREEMP_PU(0x3);
702 	tegra_dsi_writel(dsi, value, DSI_PAD_CONTROL_3);
703 
704 	return tegra_mipi_calibrate(dsi->mipi);
705 }
706 
707 static void tegra_dsi_set_timeout(struct tegra_dsi *dsi, unsigned long bclk,
708 				  unsigned int vrefresh)
709 {
710 	unsigned int timeout;
711 	u32 value;
712 
713 	/* one frame high-speed transmission timeout */
714 	timeout = (bclk / vrefresh) / 512;
715 	value = DSI_TIMEOUT_LRX(0x2000) | DSI_TIMEOUT_HTX(timeout);
716 	tegra_dsi_writel(dsi, value, DSI_TIMEOUT_0);
717 
718 	/* 2 ms peripheral timeout for panel */
719 	timeout = 2 * bclk / 512 * 1000;
720 	value = DSI_TIMEOUT_PR(timeout) | DSI_TIMEOUT_TA(0x2000);
721 	tegra_dsi_writel(dsi, value, DSI_TIMEOUT_1);
722 
723 	value = DSI_TALLY_TA(0) | DSI_TALLY_LRX(0) | DSI_TALLY_HTX(0);
724 	tegra_dsi_writel(dsi, value, DSI_TO_TALLY);
725 
726 	if (dsi->slave)
727 		tegra_dsi_set_timeout(dsi->slave, bclk, vrefresh);
728 }
729 
730 static void tegra_dsi_disable(struct tegra_dsi *dsi)
731 {
732 	u32 value;
733 
734 	if (dsi->slave) {
735 		tegra_dsi_ganged_disable(dsi->slave);
736 		tegra_dsi_ganged_disable(dsi);
737 	}
738 
739 	value = tegra_dsi_readl(dsi, DSI_POWER_CONTROL);
740 	value &= ~DSI_POWER_CONTROL_ENABLE;
741 	tegra_dsi_writel(dsi, value, DSI_POWER_CONTROL);
742 
743 	if (dsi->slave)
744 		tegra_dsi_disable(dsi->slave);
745 
746 	usleep_range(5000, 10000);
747 }
748 
749 static void tegra_dsi_soft_reset(struct tegra_dsi *dsi)
750 {
751 	u32 value;
752 
753 	value = tegra_dsi_readl(dsi, DSI_POWER_CONTROL);
754 	value &= ~DSI_POWER_CONTROL_ENABLE;
755 	tegra_dsi_writel(dsi, value, DSI_POWER_CONTROL);
756 
757 	usleep_range(300, 1000);
758 
759 	value = tegra_dsi_readl(dsi, DSI_POWER_CONTROL);
760 	value |= DSI_POWER_CONTROL_ENABLE;
761 	tegra_dsi_writel(dsi, value, DSI_POWER_CONTROL);
762 
763 	usleep_range(300, 1000);
764 
765 	value = tegra_dsi_readl(dsi, DSI_TRIGGER);
766 	if (value)
767 		tegra_dsi_writel(dsi, 0, DSI_TRIGGER);
768 
769 	if (dsi->slave)
770 		tegra_dsi_soft_reset(dsi->slave);
771 }
772 
773 static void tegra_dsi_connector_reset(struct drm_connector *connector)
774 {
775 	struct tegra_dsi_state *state = kzalloc(sizeof(*state), GFP_KERNEL);
776 
777 	if (!state)
778 		return;
779 
780 	if (connector->state) {
781 		__drm_atomic_helper_connector_destroy_state(connector->state);
782 		kfree(connector->state);
783 	}
784 
785 	__drm_atomic_helper_connector_reset(connector, &state->base);
786 }
787 
788 static struct drm_connector_state *
789 tegra_dsi_connector_duplicate_state(struct drm_connector *connector)
790 {
791 	struct tegra_dsi_state *state = to_dsi_state(connector->state);
792 	struct tegra_dsi_state *copy;
793 
794 	copy = kmemdup(state, sizeof(*state), GFP_KERNEL);
795 	if (!copy)
796 		return NULL;
797 
798 	__drm_atomic_helper_connector_duplicate_state(connector,
799 						      &copy->base);
800 
801 	return &copy->base;
802 }
803 
804 static const struct drm_connector_funcs tegra_dsi_connector_funcs = {
805 	.reset = tegra_dsi_connector_reset,
806 	.detect = tegra_output_connector_detect,
807 	.fill_modes = drm_helper_probe_single_connector_modes,
808 	.destroy = tegra_output_connector_destroy,
809 	.atomic_duplicate_state = tegra_dsi_connector_duplicate_state,
810 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
811 	.late_register = tegra_dsi_late_register,
812 	.early_unregister = tegra_dsi_early_unregister,
813 };
814 
815 static enum drm_mode_status
816 tegra_dsi_connector_mode_valid(struct drm_connector *connector,
817 			       struct drm_display_mode *mode)
818 {
819 	return MODE_OK;
820 }
821 
822 static const struct drm_connector_helper_funcs tegra_dsi_connector_helper_funcs = {
823 	.get_modes = tegra_output_connector_get_modes,
824 	.mode_valid = tegra_dsi_connector_mode_valid,
825 };
826 
827 static const struct drm_encoder_funcs tegra_dsi_encoder_funcs = {
828 	.destroy = tegra_output_encoder_destroy,
829 };
830 
831 static void tegra_dsi_unprepare(struct tegra_dsi *dsi)
832 {
833 	int err;
834 
835 	if (dsi->slave)
836 		tegra_dsi_unprepare(dsi->slave);
837 
838 	err = tegra_mipi_disable(dsi->mipi);
839 	if (err < 0)
840 		dev_err(dsi->dev, "failed to disable MIPI calibration: %d\n",
841 			err);
842 
843 	pm_runtime_put(dsi->dev);
844 }
845 
846 static void tegra_dsi_encoder_disable(struct drm_encoder *encoder)
847 {
848 	struct tegra_output *output = encoder_to_output(encoder);
849 	struct tegra_dc *dc = to_tegra_dc(encoder->crtc);
850 	struct tegra_dsi *dsi = to_dsi(output);
851 	u32 value;
852 	int err;
853 
854 	if (output->panel)
855 		drm_panel_disable(output->panel);
856 
857 	tegra_dsi_video_disable(dsi);
858 
859 	/*
860 	 * The following accesses registers of the display controller, so make
861 	 * sure it's only executed when the output is attached to one.
862 	 */
863 	if (dc) {
864 		value = tegra_dc_readl(dc, DC_DISP_DISP_WIN_OPTIONS);
865 		value &= ~DSI_ENABLE;
866 		tegra_dc_writel(dc, value, DC_DISP_DISP_WIN_OPTIONS);
867 
868 		tegra_dc_commit(dc);
869 	}
870 
871 	err = tegra_dsi_wait_idle(dsi, 100);
872 	if (err < 0)
873 		dev_dbg(dsi->dev, "failed to idle DSI: %d\n", err);
874 
875 	tegra_dsi_soft_reset(dsi);
876 
877 	if (output->panel)
878 		drm_panel_unprepare(output->panel);
879 
880 	tegra_dsi_disable(dsi);
881 
882 	tegra_dsi_unprepare(dsi);
883 }
884 
885 static void tegra_dsi_prepare(struct tegra_dsi *dsi)
886 {
887 	int err;
888 
889 	pm_runtime_get_sync(dsi->dev);
890 
891 	err = tegra_mipi_enable(dsi->mipi);
892 	if (err < 0)
893 		dev_err(dsi->dev, "failed to enable MIPI calibration: %d\n",
894 			err);
895 
896 	err = tegra_dsi_pad_calibrate(dsi);
897 	if (err < 0)
898 		dev_err(dsi->dev, "MIPI calibration failed: %d\n", err);
899 
900 	if (dsi->slave)
901 		tegra_dsi_prepare(dsi->slave);
902 }
903 
904 static void tegra_dsi_encoder_enable(struct drm_encoder *encoder)
905 {
906 	struct drm_display_mode *mode = &encoder->crtc->state->adjusted_mode;
907 	struct tegra_output *output = encoder_to_output(encoder);
908 	struct tegra_dc *dc = to_tegra_dc(encoder->crtc);
909 	struct tegra_dsi *dsi = to_dsi(output);
910 	struct tegra_dsi_state *state;
911 	u32 value;
912 
913 	tegra_dsi_prepare(dsi);
914 
915 	state = tegra_dsi_get_state(dsi);
916 
917 	tegra_dsi_set_timeout(dsi, state->bclk, state->vrefresh);
918 
919 	/*
920 	 * The D-PHY timing fields are expressed in byte-clock cycles, so
921 	 * multiply the period by 8.
922 	 */
923 	tegra_dsi_set_phy_timing(dsi, state->period * 8, &state->timing);
924 
925 	if (output->panel)
926 		drm_panel_prepare(output->panel);
927 
928 	tegra_dsi_configure(dsi, dc->pipe, mode);
929 
930 	/* enable display controller */
931 	value = tegra_dc_readl(dc, DC_DISP_DISP_WIN_OPTIONS);
932 	value |= DSI_ENABLE;
933 	tegra_dc_writel(dc, value, DC_DISP_DISP_WIN_OPTIONS);
934 
935 	tegra_dc_commit(dc);
936 
937 	/* enable DSI controller */
938 	tegra_dsi_enable(dsi);
939 
940 	if (output->panel)
941 		drm_panel_enable(output->panel);
942 }
943 
944 static int
945 tegra_dsi_encoder_atomic_check(struct drm_encoder *encoder,
946 			       struct drm_crtc_state *crtc_state,
947 			       struct drm_connector_state *conn_state)
948 {
949 	struct tegra_output *output = encoder_to_output(encoder);
950 	struct tegra_dsi_state *state = to_dsi_state(conn_state);
951 	struct tegra_dc *dc = to_tegra_dc(conn_state->crtc);
952 	struct tegra_dsi *dsi = to_dsi(output);
953 	unsigned int scdiv;
954 	unsigned long plld;
955 	int err;
956 
957 	state->pclk = crtc_state->mode.clock * 1000;
958 
959 	err = tegra_dsi_get_muldiv(dsi->format, &state->mul, &state->div);
960 	if (err < 0)
961 		return err;
962 
963 	state->lanes = tegra_dsi_get_lanes(dsi);
964 
965 	err = tegra_dsi_get_format(dsi->format, &state->format);
966 	if (err < 0)
967 		return err;
968 
969 	state->vrefresh = drm_mode_vrefresh(&crtc_state->mode);
970 
971 	/* compute byte clock */
972 	state->bclk = (state->pclk * state->mul) / (state->div * state->lanes);
973 
974 	DRM_DEBUG_KMS("mul: %u, div: %u, lanes: %u\n", state->mul, state->div,
975 		      state->lanes);
976 	DRM_DEBUG_KMS("format: %u, vrefresh: %u\n", state->format,
977 		      state->vrefresh);
978 	DRM_DEBUG_KMS("bclk: %lu\n", state->bclk);
979 
980 	/*
981 	 * Compute bit clock and round up to the next MHz.
982 	 */
983 	plld = DIV_ROUND_UP(state->bclk * 8, USEC_PER_SEC) * USEC_PER_SEC;
984 	state->period = DIV_ROUND_CLOSEST(NSEC_PER_SEC, plld);
985 
986 	err = mipi_dphy_timing_get_default(&state->timing, state->period);
987 	if (err < 0)
988 		return err;
989 
990 	err = mipi_dphy_timing_validate(&state->timing, state->period);
991 	if (err < 0) {
992 		dev_err(dsi->dev, "failed to validate D-PHY timing: %d\n", err);
993 		return err;
994 	}
995 
996 	/*
997 	 * We divide the frequency by two here, but we make up for that by
998 	 * setting the shift clock divider (further below) to half of the
999 	 * correct value.
1000 	 */
1001 	plld /= 2;
1002 
1003 	/*
1004 	 * Derive pixel clock from bit clock using the shift clock divider.
1005 	 * Note that this is only half of what we would expect, but we need
1006 	 * that to make up for the fact that we divided the bit clock by a
1007 	 * factor of two above.
1008 	 *
1009 	 * It's not clear exactly why this is necessary, but the display is
1010 	 * not working properly otherwise. Perhaps the PLLs cannot generate
1011 	 * frequencies sufficiently high.
1012 	 */
1013 	scdiv = ((8 * state->mul) / (state->div * state->lanes)) - 2;
1014 
1015 	err = tegra_dc_state_setup_clock(dc, crtc_state, dsi->clk_parent,
1016 					 plld, scdiv);
1017 	if (err < 0) {
1018 		dev_err(output->dev, "failed to setup CRTC state: %d\n", err);
1019 		return err;
1020 	}
1021 
1022 	return err;
1023 }
1024 
1025 static const struct drm_encoder_helper_funcs tegra_dsi_encoder_helper_funcs = {
1026 	.disable = tegra_dsi_encoder_disable,
1027 	.enable = tegra_dsi_encoder_enable,
1028 	.atomic_check = tegra_dsi_encoder_atomic_check,
1029 };
1030 
1031 static int tegra_dsi_init(struct host1x_client *client)
1032 {
1033 	struct drm_device *drm = dev_get_drvdata(client->parent);
1034 	struct tegra_dsi *dsi = host1x_client_to_dsi(client);
1035 	int err;
1036 
1037 	/* Gangsters must not register their own outputs. */
1038 	if (!dsi->master) {
1039 		dsi->output.dev = client->dev;
1040 
1041 		drm_connector_init(drm, &dsi->output.connector,
1042 				   &tegra_dsi_connector_funcs,
1043 				   DRM_MODE_CONNECTOR_DSI);
1044 		drm_connector_helper_add(&dsi->output.connector,
1045 					 &tegra_dsi_connector_helper_funcs);
1046 		dsi->output.connector.dpms = DRM_MODE_DPMS_OFF;
1047 
1048 		drm_encoder_init(drm, &dsi->output.encoder,
1049 				 &tegra_dsi_encoder_funcs,
1050 				 DRM_MODE_ENCODER_DSI, NULL);
1051 		drm_encoder_helper_add(&dsi->output.encoder,
1052 				       &tegra_dsi_encoder_helper_funcs);
1053 
1054 		drm_connector_attach_encoder(&dsi->output.connector,
1055 						  &dsi->output.encoder);
1056 		drm_connector_register(&dsi->output.connector);
1057 
1058 		err = tegra_output_init(drm, &dsi->output);
1059 		if (err < 0)
1060 			dev_err(dsi->dev, "failed to initialize output: %d\n",
1061 				err);
1062 
1063 		dsi->output.encoder.possible_crtcs = 0x3;
1064 	}
1065 
1066 	return 0;
1067 }
1068 
1069 static int tegra_dsi_exit(struct host1x_client *client)
1070 {
1071 	struct tegra_dsi *dsi = host1x_client_to_dsi(client);
1072 
1073 	tegra_output_exit(&dsi->output);
1074 
1075 	return 0;
1076 }
1077 
1078 static const struct host1x_client_ops dsi_client_ops = {
1079 	.init = tegra_dsi_init,
1080 	.exit = tegra_dsi_exit,
1081 };
1082 
1083 static int tegra_dsi_setup_clocks(struct tegra_dsi *dsi)
1084 {
1085 	struct clk *parent;
1086 	int err;
1087 
1088 	parent = clk_get_parent(dsi->clk);
1089 	if (!parent)
1090 		return -EINVAL;
1091 
1092 	err = clk_set_parent(parent, dsi->clk_parent);
1093 	if (err < 0)
1094 		return err;
1095 
1096 	return 0;
1097 }
1098 
1099 static const char * const error_report[16] = {
1100 	"SoT Error",
1101 	"SoT Sync Error",
1102 	"EoT Sync Error",
1103 	"Escape Mode Entry Command Error",
1104 	"Low-Power Transmit Sync Error",
1105 	"Peripheral Timeout Error",
1106 	"False Control Error",
1107 	"Contention Detected",
1108 	"ECC Error, single-bit",
1109 	"ECC Error, multi-bit",
1110 	"Checksum Error",
1111 	"DSI Data Type Not Recognized",
1112 	"DSI VC ID Invalid",
1113 	"Invalid Transmission Length",
1114 	"Reserved",
1115 	"DSI Protocol Violation",
1116 };
1117 
1118 static ssize_t tegra_dsi_read_response(struct tegra_dsi *dsi,
1119 				       const struct mipi_dsi_msg *msg,
1120 				       size_t count)
1121 {
1122 	u8 *rx = msg->rx_buf;
1123 	unsigned int i, j, k;
1124 	size_t size = 0;
1125 	u16 errors;
1126 	u32 value;
1127 
1128 	/* read and parse packet header */
1129 	value = tegra_dsi_readl(dsi, DSI_RD_DATA);
1130 
1131 	switch (value & 0x3f) {
1132 	case MIPI_DSI_RX_ACKNOWLEDGE_AND_ERROR_REPORT:
1133 		errors = (value >> 8) & 0xffff;
1134 		dev_dbg(dsi->dev, "Acknowledge and error report: %04x\n",
1135 			errors);
1136 		for (i = 0; i < ARRAY_SIZE(error_report); i++)
1137 			if (errors & BIT(i))
1138 				dev_dbg(dsi->dev, "  %2u: %s\n", i,
1139 					error_report[i]);
1140 		break;
1141 
1142 	case MIPI_DSI_RX_DCS_SHORT_READ_RESPONSE_1BYTE:
1143 		rx[0] = (value >> 8) & 0xff;
1144 		size = 1;
1145 		break;
1146 
1147 	case MIPI_DSI_RX_DCS_SHORT_READ_RESPONSE_2BYTE:
1148 		rx[0] = (value >>  8) & 0xff;
1149 		rx[1] = (value >> 16) & 0xff;
1150 		size = 2;
1151 		break;
1152 
1153 	case MIPI_DSI_RX_DCS_LONG_READ_RESPONSE:
1154 		size = ((value >> 8) & 0xff00) | ((value >> 8) & 0xff);
1155 		break;
1156 
1157 	case MIPI_DSI_RX_GENERIC_LONG_READ_RESPONSE:
1158 		size = ((value >> 8) & 0xff00) | ((value >> 8) & 0xff);
1159 		break;
1160 
1161 	default:
1162 		dev_err(dsi->dev, "unhandled response type: %02x\n",
1163 			value & 0x3f);
1164 		return -EPROTO;
1165 	}
1166 
1167 	size = min(size, msg->rx_len);
1168 
1169 	if (msg->rx_buf && size > 0) {
1170 		for (i = 0, j = 0; i < count - 1; i++, j += 4) {
1171 			u8 *rx = msg->rx_buf + j;
1172 
1173 			value = tegra_dsi_readl(dsi, DSI_RD_DATA);
1174 
1175 			for (k = 0; k < 4 && (j + k) < msg->rx_len; k++)
1176 				rx[j + k] = (value >> (k << 3)) & 0xff;
1177 		}
1178 	}
1179 
1180 	return size;
1181 }
1182 
1183 static int tegra_dsi_transmit(struct tegra_dsi *dsi, unsigned long timeout)
1184 {
1185 	tegra_dsi_writel(dsi, DSI_TRIGGER_HOST, DSI_TRIGGER);
1186 
1187 	timeout = jiffies + msecs_to_jiffies(timeout);
1188 
1189 	while (time_before(jiffies, timeout)) {
1190 		u32 value = tegra_dsi_readl(dsi, DSI_TRIGGER);
1191 		if ((value & DSI_TRIGGER_HOST) == 0)
1192 			return 0;
1193 
1194 		usleep_range(1000, 2000);
1195 	}
1196 
1197 	DRM_DEBUG_KMS("timeout waiting for transmission to complete\n");
1198 	return -ETIMEDOUT;
1199 }
1200 
1201 static int tegra_dsi_wait_for_response(struct tegra_dsi *dsi,
1202 				       unsigned long timeout)
1203 {
1204 	timeout = jiffies + msecs_to_jiffies(250);
1205 
1206 	while (time_before(jiffies, timeout)) {
1207 		u32 value = tegra_dsi_readl(dsi, DSI_STATUS);
1208 		u8 count = value & 0x1f;
1209 
1210 		if (count > 0)
1211 			return count;
1212 
1213 		usleep_range(1000, 2000);
1214 	}
1215 
1216 	DRM_DEBUG_KMS("peripheral returned no data\n");
1217 	return -ETIMEDOUT;
1218 }
1219 
1220 static void tegra_dsi_writesl(struct tegra_dsi *dsi, unsigned long offset,
1221 			      const void *buffer, size_t size)
1222 {
1223 	const u8 *buf = buffer;
1224 	size_t i, j;
1225 	u32 value;
1226 
1227 	for (j = 0; j < size; j += 4) {
1228 		value = 0;
1229 
1230 		for (i = 0; i < 4 && j + i < size; i++)
1231 			value |= buf[j + i] << (i << 3);
1232 
1233 		tegra_dsi_writel(dsi, value, DSI_WR_DATA);
1234 	}
1235 }
1236 
1237 static ssize_t tegra_dsi_host_transfer(struct mipi_dsi_host *host,
1238 				       const struct mipi_dsi_msg *msg)
1239 {
1240 	struct tegra_dsi *dsi = host_to_tegra(host);
1241 	struct mipi_dsi_packet packet;
1242 	const u8 *header;
1243 	size_t count;
1244 	ssize_t err;
1245 	u32 value;
1246 
1247 	err = mipi_dsi_create_packet(&packet, msg);
1248 	if (err < 0)
1249 		return err;
1250 
1251 	header = packet.header;
1252 
1253 	/* maximum FIFO depth is 1920 words */
1254 	if (packet.size > dsi->video_fifo_depth * 4)
1255 		return -ENOSPC;
1256 
1257 	/* reset underflow/overflow flags */
1258 	value = tegra_dsi_readl(dsi, DSI_STATUS);
1259 	if (value & (DSI_STATUS_UNDERFLOW | DSI_STATUS_OVERFLOW)) {
1260 		value = DSI_HOST_CONTROL_FIFO_RESET;
1261 		tegra_dsi_writel(dsi, value, DSI_HOST_CONTROL);
1262 		usleep_range(10, 20);
1263 	}
1264 
1265 	value = tegra_dsi_readl(dsi, DSI_POWER_CONTROL);
1266 	value |= DSI_POWER_CONTROL_ENABLE;
1267 	tegra_dsi_writel(dsi, value, DSI_POWER_CONTROL);
1268 
1269 	usleep_range(5000, 10000);
1270 
1271 	value = DSI_HOST_CONTROL_CRC_RESET | DSI_HOST_CONTROL_TX_TRIG_HOST |
1272 		DSI_HOST_CONTROL_CS | DSI_HOST_CONTROL_ECC;
1273 
1274 	if ((msg->flags & MIPI_DSI_MSG_USE_LPM) == 0)
1275 		value |= DSI_HOST_CONTROL_HS;
1276 
1277 	/*
1278 	 * The host FIFO has a maximum of 64 words, so larger transmissions
1279 	 * need to use the video FIFO.
1280 	 */
1281 	if (packet.size > dsi->host_fifo_depth * 4)
1282 		value |= DSI_HOST_CONTROL_FIFO_SEL;
1283 
1284 	tegra_dsi_writel(dsi, value, DSI_HOST_CONTROL);
1285 
1286 	/*
1287 	 * For reads and messages with explicitly requested ACK, generate a
1288 	 * BTA sequence after the transmission of the packet.
1289 	 */
1290 	if ((msg->flags & MIPI_DSI_MSG_REQ_ACK) ||
1291 	    (msg->rx_buf && msg->rx_len > 0)) {
1292 		value = tegra_dsi_readl(dsi, DSI_HOST_CONTROL);
1293 		value |= DSI_HOST_CONTROL_PKT_BTA;
1294 		tegra_dsi_writel(dsi, value, DSI_HOST_CONTROL);
1295 	}
1296 
1297 	value = DSI_CONTROL_LANES(0) | DSI_CONTROL_HOST_ENABLE;
1298 	tegra_dsi_writel(dsi, value, DSI_CONTROL);
1299 
1300 	/* write packet header, ECC is generated by hardware */
1301 	value = header[2] << 16 | header[1] << 8 | header[0];
1302 	tegra_dsi_writel(dsi, value, DSI_WR_DATA);
1303 
1304 	/* write payload (if any) */
1305 	if (packet.payload_length > 0)
1306 		tegra_dsi_writesl(dsi, DSI_WR_DATA, packet.payload,
1307 				  packet.payload_length);
1308 
1309 	err = tegra_dsi_transmit(dsi, 250);
1310 	if (err < 0)
1311 		return err;
1312 
1313 	if ((msg->flags & MIPI_DSI_MSG_REQ_ACK) ||
1314 	    (msg->rx_buf && msg->rx_len > 0)) {
1315 		err = tegra_dsi_wait_for_response(dsi, 250);
1316 		if (err < 0)
1317 			return err;
1318 
1319 		count = err;
1320 
1321 		value = tegra_dsi_readl(dsi, DSI_RD_DATA);
1322 		switch (value) {
1323 		case 0x84:
1324 			/*
1325 			dev_dbg(dsi->dev, "ACK\n");
1326 			*/
1327 			break;
1328 
1329 		case 0x87:
1330 			/*
1331 			dev_dbg(dsi->dev, "ESCAPE\n");
1332 			*/
1333 			break;
1334 
1335 		default:
1336 			dev_err(dsi->dev, "unknown status: %08x\n", value);
1337 			break;
1338 		}
1339 
1340 		if (count > 1) {
1341 			err = tegra_dsi_read_response(dsi, msg, count);
1342 			if (err < 0)
1343 				dev_err(dsi->dev,
1344 					"failed to parse response: %zd\n",
1345 					err);
1346 			else {
1347 				/*
1348 				 * For read commands, return the number of
1349 				 * bytes returned by the peripheral.
1350 				 */
1351 				count = err;
1352 			}
1353 		}
1354 	} else {
1355 		/*
1356 		 * For write commands, we have transmitted the 4-byte header
1357 		 * plus the variable-length payload.
1358 		 */
1359 		count = 4 + packet.payload_length;
1360 	}
1361 
1362 	return count;
1363 }
1364 
1365 static int tegra_dsi_ganged_setup(struct tegra_dsi *dsi)
1366 {
1367 	struct clk *parent;
1368 	int err;
1369 
1370 	/* make sure both DSI controllers share the same PLL */
1371 	parent = clk_get_parent(dsi->slave->clk);
1372 	if (!parent)
1373 		return -EINVAL;
1374 
1375 	err = clk_set_parent(parent, dsi->clk_parent);
1376 	if (err < 0)
1377 		return err;
1378 
1379 	return 0;
1380 }
1381 
1382 static int tegra_dsi_host_attach(struct mipi_dsi_host *host,
1383 				 struct mipi_dsi_device *device)
1384 {
1385 	struct tegra_dsi *dsi = host_to_tegra(host);
1386 
1387 	dsi->flags = device->mode_flags;
1388 	dsi->format = device->format;
1389 	dsi->lanes = device->lanes;
1390 
1391 	if (dsi->slave) {
1392 		int err;
1393 
1394 		dev_dbg(dsi->dev, "attaching dual-channel device %s\n",
1395 			dev_name(&device->dev));
1396 
1397 		err = tegra_dsi_ganged_setup(dsi);
1398 		if (err < 0) {
1399 			dev_err(dsi->dev, "failed to set up ganged mode: %d\n",
1400 				err);
1401 			return err;
1402 		}
1403 	}
1404 
1405 	/*
1406 	 * Slaves don't have a panel associated with them, so they provide
1407 	 * merely the second channel.
1408 	 */
1409 	if (!dsi->master) {
1410 		struct tegra_output *output = &dsi->output;
1411 
1412 		output->panel = of_drm_find_panel(device->dev.of_node);
1413 		if (IS_ERR(output->panel))
1414 			output->panel = NULL;
1415 
1416 		if (output->panel && output->connector.dev) {
1417 			drm_panel_attach(output->panel, &output->connector);
1418 			drm_helper_hpd_irq_event(output->connector.dev);
1419 		}
1420 	}
1421 
1422 	return 0;
1423 }
1424 
1425 static int tegra_dsi_host_detach(struct mipi_dsi_host *host,
1426 				 struct mipi_dsi_device *device)
1427 {
1428 	struct tegra_dsi *dsi = host_to_tegra(host);
1429 	struct tegra_output *output = &dsi->output;
1430 
1431 	if (output->panel && &device->dev == output->panel->dev) {
1432 		output->panel = NULL;
1433 
1434 		if (output->connector.dev)
1435 			drm_helper_hpd_irq_event(output->connector.dev);
1436 	}
1437 
1438 	return 0;
1439 }
1440 
1441 static const struct mipi_dsi_host_ops tegra_dsi_host_ops = {
1442 	.attach = tegra_dsi_host_attach,
1443 	.detach = tegra_dsi_host_detach,
1444 	.transfer = tegra_dsi_host_transfer,
1445 };
1446 
1447 static int tegra_dsi_ganged_probe(struct tegra_dsi *dsi)
1448 {
1449 	struct device_node *np;
1450 
1451 	np = of_parse_phandle(dsi->dev->of_node, "nvidia,ganged-mode", 0);
1452 	if (np) {
1453 		struct platform_device *gangster = of_find_device_by_node(np);
1454 
1455 		dsi->slave = platform_get_drvdata(gangster);
1456 		of_node_put(np);
1457 
1458 		if (!dsi->slave)
1459 			return -EPROBE_DEFER;
1460 
1461 		dsi->slave->master = dsi;
1462 	}
1463 
1464 	return 0;
1465 }
1466 
1467 static int tegra_dsi_probe(struct platform_device *pdev)
1468 {
1469 	struct tegra_dsi *dsi;
1470 	struct resource *regs;
1471 	int err;
1472 
1473 	dsi = devm_kzalloc(&pdev->dev, sizeof(*dsi), GFP_KERNEL);
1474 	if (!dsi)
1475 		return -ENOMEM;
1476 
1477 	dsi->output.dev = dsi->dev = &pdev->dev;
1478 	dsi->video_fifo_depth = 1920;
1479 	dsi->host_fifo_depth = 64;
1480 
1481 	err = tegra_dsi_ganged_probe(dsi);
1482 	if (err < 0)
1483 		return err;
1484 
1485 	err = tegra_output_probe(&dsi->output);
1486 	if (err < 0)
1487 		return err;
1488 
1489 	dsi->output.connector.polled = DRM_CONNECTOR_POLL_HPD;
1490 
1491 	/*
1492 	 * Assume these values by default. When a DSI peripheral driver
1493 	 * attaches to the DSI host, the parameters will be taken from
1494 	 * the attached device.
1495 	 */
1496 	dsi->flags = MIPI_DSI_MODE_VIDEO;
1497 	dsi->format = MIPI_DSI_FMT_RGB888;
1498 	dsi->lanes = 4;
1499 
1500 	if (!pdev->dev.pm_domain) {
1501 		dsi->rst = devm_reset_control_get(&pdev->dev, "dsi");
1502 		if (IS_ERR(dsi->rst))
1503 			return PTR_ERR(dsi->rst);
1504 	}
1505 
1506 	dsi->clk = devm_clk_get(&pdev->dev, NULL);
1507 	if (IS_ERR(dsi->clk)) {
1508 		dev_err(&pdev->dev, "cannot get DSI clock\n");
1509 		return PTR_ERR(dsi->clk);
1510 	}
1511 
1512 	dsi->clk_lp = devm_clk_get(&pdev->dev, "lp");
1513 	if (IS_ERR(dsi->clk_lp)) {
1514 		dev_err(&pdev->dev, "cannot get low-power clock\n");
1515 		return PTR_ERR(dsi->clk_lp);
1516 	}
1517 
1518 	dsi->clk_parent = devm_clk_get(&pdev->dev, "parent");
1519 	if (IS_ERR(dsi->clk_parent)) {
1520 		dev_err(&pdev->dev, "cannot get parent clock\n");
1521 		return PTR_ERR(dsi->clk_parent);
1522 	}
1523 
1524 	dsi->vdd = devm_regulator_get(&pdev->dev, "avdd-dsi-csi");
1525 	if (IS_ERR(dsi->vdd)) {
1526 		dev_err(&pdev->dev, "cannot get VDD supply\n");
1527 		return PTR_ERR(dsi->vdd);
1528 	}
1529 
1530 	err = tegra_dsi_setup_clocks(dsi);
1531 	if (err < 0) {
1532 		dev_err(&pdev->dev, "cannot setup clocks\n");
1533 		return err;
1534 	}
1535 
1536 	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1537 	dsi->regs = devm_ioremap_resource(&pdev->dev, regs);
1538 	if (IS_ERR(dsi->regs))
1539 		return PTR_ERR(dsi->regs);
1540 
1541 	dsi->mipi = tegra_mipi_request(&pdev->dev);
1542 	if (IS_ERR(dsi->mipi))
1543 		return PTR_ERR(dsi->mipi);
1544 
1545 	dsi->host.ops = &tegra_dsi_host_ops;
1546 	dsi->host.dev = &pdev->dev;
1547 
1548 	err = mipi_dsi_host_register(&dsi->host);
1549 	if (err < 0) {
1550 		dev_err(&pdev->dev, "failed to register DSI host: %d\n", err);
1551 		goto mipi_free;
1552 	}
1553 
1554 	platform_set_drvdata(pdev, dsi);
1555 	pm_runtime_enable(&pdev->dev);
1556 
1557 	INIT_LIST_HEAD(&dsi->client.list);
1558 	dsi->client.ops = &dsi_client_ops;
1559 	dsi->client.dev = &pdev->dev;
1560 
1561 	err = host1x_client_register(&dsi->client);
1562 	if (err < 0) {
1563 		dev_err(&pdev->dev, "failed to register host1x client: %d\n",
1564 			err);
1565 		goto unregister;
1566 	}
1567 
1568 	return 0;
1569 
1570 unregister:
1571 	mipi_dsi_host_unregister(&dsi->host);
1572 mipi_free:
1573 	tegra_mipi_free(dsi->mipi);
1574 	return err;
1575 }
1576 
1577 static int tegra_dsi_remove(struct platform_device *pdev)
1578 {
1579 	struct tegra_dsi *dsi = platform_get_drvdata(pdev);
1580 	int err;
1581 
1582 	pm_runtime_disable(&pdev->dev);
1583 
1584 	err = host1x_client_unregister(&dsi->client);
1585 	if (err < 0) {
1586 		dev_err(&pdev->dev, "failed to unregister host1x client: %d\n",
1587 			err);
1588 		return err;
1589 	}
1590 
1591 	tegra_output_remove(&dsi->output);
1592 
1593 	mipi_dsi_host_unregister(&dsi->host);
1594 	tegra_mipi_free(dsi->mipi);
1595 
1596 	return 0;
1597 }
1598 
1599 #ifdef CONFIG_PM
1600 static int tegra_dsi_suspend(struct device *dev)
1601 {
1602 	struct tegra_dsi *dsi = dev_get_drvdata(dev);
1603 	int err;
1604 
1605 	if (dsi->rst) {
1606 		err = reset_control_assert(dsi->rst);
1607 		if (err < 0) {
1608 			dev_err(dev, "failed to assert reset: %d\n", err);
1609 			return err;
1610 		}
1611 	}
1612 
1613 	usleep_range(1000, 2000);
1614 
1615 	clk_disable_unprepare(dsi->clk_lp);
1616 	clk_disable_unprepare(dsi->clk);
1617 
1618 	regulator_disable(dsi->vdd);
1619 
1620 	return 0;
1621 }
1622 
1623 static int tegra_dsi_resume(struct device *dev)
1624 {
1625 	struct tegra_dsi *dsi = dev_get_drvdata(dev);
1626 	int err;
1627 
1628 	err = regulator_enable(dsi->vdd);
1629 	if (err < 0) {
1630 		dev_err(dsi->dev, "failed to enable VDD supply: %d\n", err);
1631 		return err;
1632 	}
1633 
1634 	err = clk_prepare_enable(dsi->clk);
1635 	if (err < 0) {
1636 		dev_err(dev, "cannot enable DSI clock: %d\n", err);
1637 		goto disable_vdd;
1638 	}
1639 
1640 	err = clk_prepare_enable(dsi->clk_lp);
1641 	if (err < 0) {
1642 		dev_err(dev, "cannot enable low-power clock: %d\n", err);
1643 		goto disable_clk;
1644 	}
1645 
1646 	usleep_range(1000, 2000);
1647 
1648 	if (dsi->rst) {
1649 		err = reset_control_deassert(dsi->rst);
1650 		if (err < 0) {
1651 			dev_err(dev, "cannot assert reset: %d\n", err);
1652 			goto disable_clk_lp;
1653 		}
1654 	}
1655 
1656 	return 0;
1657 
1658 disable_clk_lp:
1659 	clk_disable_unprepare(dsi->clk_lp);
1660 disable_clk:
1661 	clk_disable_unprepare(dsi->clk);
1662 disable_vdd:
1663 	regulator_disable(dsi->vdd);
1664 	return err;
1665 }
1666 #endif
1667 
1668 static const struct dev_pm_ops tegra_dsi_pm_ops = {
1669 	SET_RUNTIME_PM_OPS(tegra_dsi_suspend, tegra_dsi_resume, NULL)
1670 };
1671 
1672 static const struct of_device_id tegra_dsi_of_match[] = {
1673 	{ .compatible = "nvidia,tegra210-dsi", },
1674 	{ .compatible = "nvidia,tegra132-dsi", },
1675 	{ .compatible = "nvidia,tegra124-dsi", },
1676 	{ .compatible = "nvidia,tegra114-dsi", },
1677 	{ },
1678 };
1679 MODULE_DEVICE_TABLE(of, tegra_dsi_of_match);
1680 
1681 struct platform_driver tegra_dsi_driver = {
1682 	.driver = {
1683 		.name = "tegra-dsi",
1684 		.of_match_table = tegra_dsi_of_match,
1685 		.pm = &tegra_dsi_pm_ops,
1686 	},
1687 	.probe = tegra_dsi_probe,
1688 	.remove = tegra_dsi_remove,
1689 };
1690